Sprinklers are commonly used for landscape irrigation. It is common for a sprinkler to include a stem with an inlet at one end and a nozzle attached to the other end. One type of stem is a fixed stem. With the fixed stem, one end is connected to a water supply, usually at a point below ground, and the other end extends above ground and is fixed with the nozzle.
Another type of stem is used in a “pop-up” sprinkler as a riser. A pop-up sprinkler is typically buried in the ground and includes a stationary housing and a riser, mounted within the housing. During an irrigation cycle, the riser is propelled through an open upper end of the housing and projects above ground level, or “pops up,” to distribute water to surrounding terrain. More specifically, pressurized water is supplied to the sprinkler through a water supply line attached to an inlet of the housing. The pressurized water causes the riser to travel upwards against the bias of a spring to the elevated spraying position above the sprinkler housing to distribute water to surrounding terrain through one or more spray nozzles. When the irrigation cycle is completed, the pressurized water supply is shut off, and the riser is spring-retracted back into the sprinkler housing so that the top of the nozzle, which is attached to the riser, is at or slightly below ground level.
Pop-up sprinklers and other types of sprinklers are frequently shipped and initially operated with a flush cap mounted on the stem or riser, as opposed to a nozzle. The flush cap protects the sprinkler during shipping and reduces the amount of dirt and debris that can enter into the sprinkler. Following installation of the sprinkler, water is initially discharged through the sprinkler to flush out any debris that may have accumulated inside the system. The flush cap is then replaced with a desired nozzle, and the sprinkler is then operated for normal landscape irrigation.
One concern in landscape irrigation is minimizing water waste and loss. Water conservation has become increasingly significant in landscape irrigation. Many communities have regulations on the use of water for landscape irrigation.
Water loss is a major concern if a significant volume of water is discharged when the nozzle on the stem or riser of a pop-up sprinkler is removed or damaged. For example, a user may remove the sprinkler nozzle when changing to a different nozzle or during routine maintenance. Alternatively, a vandal may intentionally damage the sprinkler or cause the nozzle to become partially or completely detached. For instance, children may remove nozzles to unleash a geyser of water for their amusement, especially with respect to sprinklers installed in schools and public areas, such as parks and recreational fields. The damage or removal may not be immediately evident to the user and may result in continued loss of water over an extended period of time. In both instances, this discharge of water may result in flooding or overwatering in certain areas, causing damage to the landscape such as due to puddles or the impact of the water on shrubs and turf, and may also result in underwatering in other areas, especially where the sprinkler is part of a network and other sprinklers experience a decrease in water pressure.
This concern with water loss in landscape irrigation has become even more pronounced with the increased use of reclaimed water for landscape irrigation. Reclaimed water allows communities to more efficiently use their water resources for different purposes, including landscaping. Many communities have laws and regulations that limit the waste and runoff of reclaimed water. It is therefore desirable to design and install irrigation sprinklers that reduce the possibility of flooding and overwatering, thereby increasing the safe use and handling of reclaimed water and compliance with local law.
Accordingly, it would be desirable to include a flow control device for use in a stem or riser of a pop-sprinkler. It would be desirable to include a flow control device that automatically reduces the flow of water through the sprinkler (and subsequent water loss) when the nozzle is detached from the rest of the sprinkler, such as due to the routine exchange of nozzles, due to maintenance, or due to vandalism or other damage to the nozzle. Further, it would be desirable to have a flow control device that can signal nozzle removal or damage to the user to allow prompt action. It also would be desirable develop a flow control device that can be used in conjunction with a flush cap during initial flushing of the sprinkler.